Altman is the president of Y Combinator, one of the biggest VC funds in the US. Y Combinator has backed Airbnb, Dropbox, Zenefits and Stripe.

Paul Graham, Altman's cofounder at Y Combinator (who also happens to be English) suggested that the Ritz incident meant that London just wasn't on the same level as San Francisco and Northern California:

It's likely that Graham was trolling because he is English, and thus knows full well that you cannot just show up at the world's most famous hotel dressed however you like.

But the tweets started a semi-serious debate on Twitter about the way tech funding has changed San Francisco but not London. Altman and Graham's tweets prompted dozens of responses. Benedict Evans, the cantankerous analyst at Silicon Valley VC fund Andreessen Horowitz (another transplanted Brit), suggested Altman was in the wrong place:

Because this took place on Twitter, some people took it waaay too seriously, with Americans generally arguing that dress codes for bars are outdated and Brits generally arguing that Americans don't know high standards when they see them: